Environment groups and the Greens have called for the winner of Saturday’s election to review the Adani mine decision, after it emerged pressure was put on the CSIRO to accept the government’s approval of the mine’s groundwater plans.

The ABC reported on Tuesday that emails it obtained under freedom-of-information laws revealed the agency had a single afternoon to accept the federal government’s approval of Adani’s groundwater management plan.

Bill Shorten said on Tuesday that Labor would not review the government’s decision if it won the election but that the environment minister, Melissa Price, needed to come forward to answer questions.

“I don’t think she has given one national press conference,” he said. “Something on Instagram is not actually answering questions, is it?

“I do think that she needs to come forward to deal with these matters and to explain and account for [herself].”

Price signed off on Adani’s groundwater management plan immediately before the prime minister, Scott Morrison, called the election for 18 May. At the time, she said she had assurances from both Geoscience Australia and the CSIRO that the plans had met strict scientific guidelines.

But correspondence from both agencies has since raised questions about the government’s account of events that led up to the approval.

The ABC reported in April that correspondence from Geoscience Australia showed Adani had refused to accept several of the agency’s recommendations.

The CSIRO emails it published show the the agency avoided giving any categorical advice that concerns raised by its scientists had been addressed.

The agency’s research director, Warwick McDonald, wrote he had “been careful about not being categoric about the degree [to which] these responses will satisfy the recommendations”.

The Greens’ environment spokeswoman, Sarah Hanson-Young, said the documents showed Price “has been caught out lying about scientific advice”.

She said the entire process needed to be reviewed after the election.

“Melissa Price dropped the Adani carbon bomb and walked off never to be heard of again,” Hanson-Young said. “She won’t front up to answer questions at a time when we’re learning more and more about our biodiversity and extinction crisis, and the climate emergency. It is simply unacceptable.

“If she can’t do her job, she should be sacked. She is unfit for the job. This is an environmental scandal.”

Morrison defended the government, telling a press conference CSIRO and Geoscience Australia had taken part in an earlier review of the plans and they had later confirmed Adani had met requirements before being granted final approval.

“If they don’t want to support something, then they won’t, and they certainly wouldn’t do that in writing if they weren’t 100% behind it,” he said.

“And they did.”

The Australian Conservation Foundation said it was clear there was pressure on the CSIRO to back the plans and provide cover for Price’s decision and voters were right to be concerned the process had been politicised.

“Whatever its stripes, the next Australian government must review the approval of Adani’s groundwater plan – and others issued to the company – immediately after the election,” Christian Slattery, the ACF’s Stop Adani campaigner, said.

“Australians are right to be concerned about the process behind the last-minute Adani groundwater sign off and in turn all other federal environmental approvals issued to the company to dig its massive new coalmine.”

A spokesman for the Price reiterated the government’s past statements that the Carmichael project had been subject to the most rigorous assessment of any Australian mining project under federal environment law.

“In assessing Adani’s groundwater management plans, the government followed a rigorous process, with the Department of the Environment and Energy commissioning independent technical and scientific advice from Geoscience Australia and the CSIRO,” he said. “Adani made revisions to its plans based on issues raised and recommendations made by Geoscience Australia and the CSIRO.

“The Department of the Environment and Energy recommended the minister approve Adani’s plans. Geoscience Australia and the CSIRO provided further written advice that the revised plans addressed the issues raised in relation to the ground water management plans.”